Officials with the Sawtooth National Forest Avalanche Center in Ketchum are warning out-of-bounds-hungry skiers and boarders that significant avalanche danger is still widespread throughout the Wood River Valley's backcountry.
In a news release written by avalanche center Director Janet Kellam, backcountry recreationists are advised to take personal responsibility to avoid avalanche danger. Kellam stated that even on bright and sunny days, avalanche dangers still exists.
She stated that the nature of the current weak, buried layer of snow will allow slides to be triggered even from below or from adjacent terrain.
In the south and central areas of the Wood River Valley, Kellam estimated the avalanche danger to be considerable. In those areas, the snowpack is slowly adjusting to the new snow load, but is still unstable in many locations, she stated.
Human-triggered avalanches are probable on steep or wind-loaded slopes, avalanche center officials also warn.
"The recent series of storms has created prime avalanche conditions," avalanche center forecaster Matt Lutz said. "Very thin and weak snowpack on the ground has been loaded with new snow along with additional wind loading of wind-blown snow."
Lutz said that while there will be fewer avalanches with future storms, avalanches that do occur will be much larger.
In the news release, avalanche center officials stated that contrary to common speculation, the Castle Rock Fire and the accompanying backburning operations have not been the cause of the recent avalanches. Rather, they stated, weak layering within the snowpack, new snowloads and wind are responsible. They pointed out that avalanches in the area are also occurring outside of the burned areas.
However, officials added, lack of undergrowth may have played a role in the size of some of the avalanches that have run recently.
In the north valley and in the Sawtooth Mountains, officials have estimated the avalanche danger to be moderate, with some areas of greater danger. Up to three feet of new snow has fallen there, they said.
Because those areas had a generally deeper and stronger snowpack prior to the last storm, it has been better able to adjust. However, human-triggered slides are still possible on steep, rocky or wind-loaded terrain or in areas where new snow is sitting on sugary, weak, old snow.
For the most up-to-date avalanche forecast from the center, log on to www.avalanche.org or call 622-8027.